Pattern lever relieving device



Feb. 4, 1969 F. c. WIESINGER ET L 3,

PATTERN LEVER RELIEVING DEVICE Filed Dec. 6, 1967 INV EN TOR.

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FM M a United States Patent 3 Claims ABSTRACT OF THE DISCLOSURE A holdover cam for the selecting levers of a knitting machine patterning mechanism for influencing those levers not selected to initiate a knitting function at a particular feeding station. A cam for lifting non-selected pattern levers out of contact with the pattern card during the interval when selections are not possible.

Background of the invention The invention relates to the pivotally supported sensing levers of a patterning mechanism which react to spaced holes in an endless pattern card, punched according to a design, for actuating individually the instrumentalities of a knitting machine. It relates particularly to a relieving cam for assuming control of the sensing levers which may not have been selected by the pattern card and for placing them in an inactive position until a subsequent sensing action takes place.

In patterning mechanisms for independent needle knitting machines which use endless perforated pattern cards on grooved rotating drums, it is well known to provide a series of pivotally supported levers disposed to sense and react to the presence of perforations when in alignment individually therewith. It is usual in such devices to spring bias one end of each lever with its downwardly depending pin toward the upper surf-ace of the rotating pattern card until it encounters a perforation and is actuated thereby. Those levers not encountering a perforation would remain in pressure contact with the pattern card during its continuing rotation. It has been found that, even with pattern cards of comparatively non-abrasive material, frictional wear has made early replacement of pins necessary in order to avoid malfunction of the patterning mechanism.

Summary of the invention This invention provides a holdover cam for pivoting to an inactive position each lever not selected by the pattern card and for holding those non-selected levers inactive until the subsequent selection may be made. The perforations of the pattern are arranged to overlie the grooves when the card is rotated by the drum. In the present instance a pair of adjacent helical grooves provide the opportunity for a single selection by each lever in the patterning mechanism. To reduce space requirements, alternate levers when selected are actuated by the first groove of each pair and the intermediate levers by the second groove. As the pattern card passes beneath any one lever, there is an interval on the card when a selection might occur. This interval is between a point just Ibefore the levers effective groove and a second point just beyond that groove. There is also a non-selective interval following that second point and extending to a third point just before that levers subsequent effective groove where no selection is possible and where the sensing function can be relieved.

It is the general object of the invention to provide a holdover cam for controlling non-selected patterning 3,425,244 Patented Feb. 4, 1969 levers out of contact with the card during spaced intervals when selection is not possible.

It is a further object of the invention to reduce frictional wear on the patterning lever pins by raising the non-selected levers slightly at regular intervals during pattern card rotation.

These and other objects of the invention will become apparent as further details are disclosed.

Brief description of the drawing The invention will be described in greater detail by reference to a specific embodiment thereof as shown in the accompanying figures of drawing, wherein:

FIG. 1 is a vertical section of a portion of a circular knitting machine with the invention applied thereto;

FIG. 2 is a front elevation of the cams shown in FIG. 1;

FIG. 3 is a bottom plan view from FIG. 2;

FIG. 4 shows the cams as seen in FIG. 1 but with a selected lever in two positions; and

FIG. 5 is an end view of a pattern drum to illustrate the pattern sensing interval and the interval when the lever is relieved.

Description of the prefered embodiment Now referring to FIG. 1, a section of the lower cylinder 10 of a knitting machine is shown with the side wall of a typical needle slot 11 in readiness for receipt of the usual knitting instrumentalities (not shown). A fixed base member 12 pivotally supports a plurality of lifting levers 13, each having an inwardly directed lever end 14 disposed within a particular slot 11 for vertical movement therein. A series of selecting levers 15 (one shown), pivotally and slidably supported upon a rod 16, is positioned by guiding blades 17 so that the inwardly projected end of each selecting lever 15 is directly above the end 18 of one lifting lever 13. All of the selecting levers 15 of a series extend outwardly above a Jacquard type selecting mechanism, shown here only as a continually rotating drum 19 having helical grooves 20 extending the full length of the outer surface 21. An endless pattern card 22 is driven by the drum 19 for selecting levers 1'5 individually in a patterned sequence. The pattern card 22 is perforated so as to pass beneath the preferred selecting lever 15 in a manner well known in this art and each perforation will overlie one of the grooves 20. Each selecting lever 15 has a spring biased lever pin 23 directed downwardly and urged into contact with the pattern card 22 by any means such as a spring (not shown) fastened to a book 24 at the end of the selecting lever 15. With such an indicating mechanism, a pin 23, when encountering a perforation, will move the lever 15 longitudinally toward the cylinder 10 to a selected position to be activated by a raising cam 25 which will be further explained below. The selecting levers, not encountering a perforation at a particular groove 20, will remain in the sensing position shown in FIG. 1 and be controlled by the instant invention.

A rotating disc 26 encircles the stationary cylinder 10 and carries a downwardly projecting arm 27 which has the raising cam 25 fixed in depending position by screws 28 (FIGS. 2 and 4). The raising cam 25, in following its rotative path, will contact each of the levers 15 which have been moved to the selected position as seen in the solid line drawing of FIG. 4. As the raising cam 25 advances, the levers 15 will pivot to the position 15' and will in turn activate their individual lifting levers 13 by lowering the end 18 and lifting the lever end 14 to the upper position 14' in FIG. 1.

Fastened to the arm 27 by screws 29 (FIGS. 2 and 4) in overlapping relationship with the raising cam 25- is a holdover cam 30 for controlling those selecting levers 15 which remain in their sensing position (FIG. 1) due to non-selection by the pattern card 22. As the holdover cam 30 advances, the selecting levers 15 (FIG. 2) will ride down the cam surface 31 which pivots the levers 15 to the dotted line position shown in FIG. 1. This pivotal movement is insufficient to activate the lifting levers 13, but will elevate the selecting levers 15 and lever pins 23 to an inactive position away from contact with the pattern card 22. The selecting levers 15 will be held in the inactive position by the horizontal cam surface 32 and will be lowered to their sensing position by following the cam fall 33.

In FIG. it will be seen that the helical grooves 20 are positioned in pairs because of space requirements, so that alternate selecting levers may be acted upon by a first groove and the intermediate selecting levers by the second groove of each pair. In FIG. 1 a single alternate lever 15 is shown with its lever pin 23 penetrating the card 22 prior to being activated. It will be understood that the next adjacent or intermediate lever 15 (not shown) would have its lever pin 23 offset forwardly so as to be directly above the second groove of that particular pair.

The pattern is laid out upon the card 22 by having a perforation present above the groove which acts upon a particular lever 15. There is a considerable interval along the length of the card to where a subsequent perforation could be placed. It is only necessary for a lever 15 and its pin 23 to sense for a perforation during that interval of drum rotation where a perforation could occur. In FIG. 5 the interval A designates the interval where the spring biased lever pin 23 should bear upon the card to sense the presence of a perforation. In the interval B no perforation would be present in any case so no sensing by the lever 15 is necessary. Interval C shows the measured extent of rotation for an intermediate sensing lever to bear upon the card and interval D that where a sensing operation is not needed.

In operation, the clockwise rotating drum (FIG. 1) presents perforations in the pattern card to certain selecting levers 15 which are moved into the path of the raising cam 25 and thereby activate the lifting levers 13. Those selecting levers 15 not finding a perforation during a sensing interval are pivoted by the holdover cam 30 for a longer interval to an inactive position above and out of contact with the pattern card. The inactive position is held until the subsequent sensing interval is rotated into range and the cycle is repeated. By pivoting the sensing levers out of contact during the inactive interval, which exceeds the sensing interval, pin wear and replacement costs have been considerably reduced.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This invention is, therefore, not to be limited to the precise details described, but is intended to embrace all variations and modifications thereof falling within the spirit of the invention and the scope of the claims.

We claim:

1. In a circular knitting machine with a stationary cylinder having needle slots therein, a pivotally supported lifting lever for each one of said slots, selecting levers for activating individually each of said lifting levers, a continuously rotating endless pattern card having perforations for determining selecting levers for activation, an indicator means upon each of said selecting levers for penetrating said pattern card when encountering a perforation, said selecting levers being movable between a sensing position and a selected position by said pattern card, a raising cam for pivotally activating only those selecting levers which Were moved to said selected position, and a holdover cam for pivoting to an inactive position away from said pattern card those selecting levers which were not selected for activation but which remained in said sensing position.

2. Mechanism as defined in claim 1 wherein said selecting levers are permitted to bear upon said pattern card during passage of a first measured interval of rotation and are pivoted by said holdover cam to said inactive location during passage of a second measured interval of rotation by said pattern card, and wherein the extent of said second measured interval exceeds that of said first measured interval.

3. Mechanism as defined in claim 1 wherein said holdover cam includes a gradual cam fall surface for controlling the return of said selecting levers to said sensing position.

References Cited UNITED STATES PATENTS 1,670,791 5/1928 Wildt et al. 66-50 1,933,542 11/1933 Albertman et al. 66-25 WM. CARTER REYNOLDS, Primary Examiner. 

